Mapping the Green Book (MGB) began as a research project with a deceptively straightforward objective: To map the sites that were listed in the Green Book—the hotels, restaurants, gas stations, hair salons, nightclubs, drugstores in every state that were known to welcome black patrons. It is a map, in text form, of the changing landscape of racialized space across nearly three decades. As a record of the American built environment during a time of racial transformation, it is an extraordinary artifact.

It is not possible to understand the places the Green Book and other travel guides made without understanding the context within which directories were published and used, or without understanding how black travelers fit into and created an economy of tourism. This is the work the researchers behind Driving While Black have undertaken, and the MGB project sits squarely inside and alongside these histories. But MGB comes at this history from a different angle.

This image is a copy of publication from 1942, "Travel Guide of Negro Hotels and Guest Houses.," which included an ad for the affiliated Afro Travel Bureau in Baltimore, Maryland.

As an architectural and landscape historian, my project focuses on the built environment—the buildings and the people that built, adapted, and used them. The gas stations, hotels, restaurants, beauty parlors, and other businesses are what is known in my field as vernacular architecture—the buildings not designed by architects but by the ordinary men and women who needed them. Studying the buildings within the context of vernacular architecture allows me to draw on the work of many other historians, including Dell Upton, Dianne Harris, Andrew Karhl, and Ned Kauffmann, to name just a few, in figuring out how to recognize and interpret the buildings recorded in the Green Book and other travel guides.

Since I began the MGB project in 2012 as a post-doctoral fellow at the National Museum of African American History and Culture, I’ve expanded it to include other guides, particularly Travel Guide, a publication of the Afro-American Newspaper company. But my research methodology hasn’t changed much. Much of my work involves driving around with a list of addresses in my GPS, looking for buildings that aren’t there anymore. (Many black business districts that once thrived in many U.S. cities were erased either by development and urban renewal, or through disuse after the Civil Rights Act made shopping in white districts possible for black patrons). But I’ve quickly learned that when you are studying the racial landscape of U.S. history, absence is as significant as presence.

Part of that process is understanding what kinds of questions to ask when I find a building, or an empty lot that was listed in a travel guide, and one of the first things I take account of is the neighborhood context. What else was nearby? What kind of area is this—residential? commercial? or are along a highway? The second step is understanding how that neighborhood, building, or block, relates to the white neighborhoods nearby. Is the connection between the physical geography and the racial geography very apparent? Often, in the districts that were once (and often are still) primarily black, there are obvious barriers—railroad tracks are the most common, but also industrial manufacturing, electric power stations, rivers, valleys, and other obstacles, especially highways. These are the elements that often, but not always, separated and segregated black neighborhoods from the areas where white people lived and worked. Back home, when I look at the Sanborn Insurance Maps from the first part of the 20th century, those boundaries are more explicit, but I like to look first, with no preconceptions.

The La Dale Motel in Los Angeles, California, appeared in several editions of the Green Book. This photo, from 2014, reveals a remarkably intact building that retains its function as a motel.

In researching sites, I am aided by (and indebted to) the many people who have written me with information about buildings from the Green Book in their town. The project is informally crowdsourced, and when the MGB map is fully built out online, it will include an app for the public to submit data and photos for buildings they’ve researched. This is very important: When you are doing this kind of work, you are highly reliant on memories and personal archives. This is the most important evidence, and most of it is in people’s homes rather than in historical societies and archives. Excavating this history from the people who lived it is critical to preserving it.

While the work on the map continues apace, the MGB project is moving into a new phase. I’m collaborating with the brilliant and talented photographer Sahar Coston-Hardy, and we are in the process of applying for grants to fund travel to Missouri next fall. We hope to document the journey of one family who owned a Green Book hotel, as they traveled across the country during Jim Crow. We are planning to document four journeys altogether, which will become an exhibition and online publication.

When I am driving around unfamiliar cities looking for Green Book sites, and asking questions about context, boundaries, and racial geography, there is always one question underlying all the others: Why? Why are things the way they are? Working on Mapping the Green Book allows me to look for answers to that question.

Jennifer Reut is the creator of the project and blog Mapping the Green Book, which maps locations in The Negro Motorist Green Book and Travelguide. She works as a post-doctoral fellow at the National Museum of African American History and Culture, gathering data. She is also serving as a Humanities Advisor for this documentary.

If you’d like to experience The Negro Motorist Green Book first hand, there’s good news. The New York Public Library recently digitized and posted over 20 copies of The Green Book on their website. This effort is thanks to the Schomberg Center for Research in Black Culture, which worked to digitize the library’s entire collection of Green Books so they would be accessible to the public. As of now, visitors to the website can read issues from 1937 to 1963.

The books include advertisements and recommendations for hotels, service centers, restaurants, and other attractions that were welcoming and safe for African American travelers. Safe spots were listed by state and city, so motorists could plan trips to a variety of locations around the country. The guides also provided advice and information on models of automobiles and tips for maintenance and preparedness for car troubles on the road.

Throughout the books, letters and anecdotes show how important and valuable The Green Book was to African American travelers. In the 1940 issue, a letter to the editor, Victor Green, reads:

“It is a great pleasure for me to give credit where credit is due. Many of my friends have joined me in admitting that ‘The Negro Motorist Green Book’ is a credit to the Negro Race. It is a book badly needed among our Race since the advance of the motor age. Realizing the only way we knew where and how to reach our pleasure resorts was in a way of speaking, by word of mouth, until the publication of ‘The Negro Motorist Green Book.’ With our wishes of your success, and your earnest efforts. We earnestly believe ‘The Negro Motorist Green Book’ will mean as much if not more to us as the A.A.A means to the white race.”

In the 1947 issue, James A. Jackson, a representative of Esso Marketers says:

“’If there had been any such publication as this when I started travelling ‘way back in the Nineties, I would have missed a lot of anxieties, worries, and saved a lot of mental energy which, had it been conserved and used solely to the advancement of the business interests for which I traveled, my years ‘on the road’ might have been concluded long ago, with enough savings to permit my living a life of peace and quiet, now that I am becoming an old codger.’”

Read more letters and stories like these, and check out which businesses The Green Book recommended in your area by visiting The Green Book Collection on the New York Public Library Website.